Work machines may include, as non-limiting examples, hydraulic excavators, backhoe loaders, and wheel loaders. These work machines commonly have work tools pivotally attached to them. Hydraulic excavators and backhoe loaders, for example, may have digging buckets pivotally attached to the end of the machine's boom and stick. The bucket curls about its pivotal attachment to the stick under the force of a hydraulic cylinder to penetrate the soil and scoop it into the bucket. Wheel loaders, as another example, may have front buckets pivotally attached to the end of the loader's linkage. The bucket can tilt relative to the linkage under the force of a hydraulic cylinder to scoop soil out of a pile and into the bucket.
The pivotal attachment of these work tools is typically accomplished using a pin joint. A pin passes through both the machine and the work tool to hold the two together. The pin permits pivoting of the work tool and machine relative to one another, but prevents other relative motion. The machine and the work tool each include bores in which the pin is positioned.
The size of the bores in the machine and the work tool must correspond to the size of the pin. Different manufacturers may use pins with different diameters. Even among a single manufacturer's product line, different size machines may use pins of different diameters.
A work tool often cannot be easily used on a machine for which it was not originally sized, because the pin bore on the work tool does not correspond to the size of the pin for that machine. Thus, each machine may have a set of standard work tools which are sized for mounting to that particular machine. But it is difficult to mount any non-standard work tool to the machine. A work tool might be remachined to enlarge the pin bores formed on it so it can mount to a pin of a different diameter, but this would be an expensive and time consuming solution.